Tmetn-inorganic nitrate explosives blended with petroleum oil

ABSTRACT

EXPLOSIVE MIXTURES ARE PROVIDED, BASED ON TRIMETHYLXXX ETHANE TRINITRATE AND AN INORGANIC NITRATE, IN WHICH TXX RATE OF DETONATION AND, OPTIONALLY, ALSO SENSITIVITY, AXX CONTROLLED BY THE USE OF PETROLEUM OIL IN FORMULATING TXX EXPLOSIVE.

3,580,750 TMETN-IN ORGANIC NITRATE EXPLOSIVES BLENDED WITH PETROLEUM OILGeorge L. Griiiith, Coopersburg, Pa., assignor t Commercial SolventsCorporation, Terre Haute, Ind. No Drawing. Filed Oct. 7, 1968, Ser. No.765,615 Int. Cl. (106i) /00 U.S. Cl. 14938 18 Claims ABSTRACT OF THEDISCLOSURE Explosive mixtures are provided, based on trimethylolethanetrinitrate and an inorganic nitrate, in which the rate of detonationand, optionally, also sensitivity, are controlled by the use ofpetroleum oil in formulating the explosive.

A process also is provided for controlling the rate of detonation, andoptionally, sensitivity of such explosive mixtures, by mixing theinorganic nitrate with the trimethylolethane trinitrate at a temperaturewithin the range from about 100 to about 150 F., in the presence of thepetroleum oil in an appropriate amount.

This invention relates to explosive mixtures comprisingtrimethylolethane trinitrate and ammonium nitrate or other inorganicnitrate, having a controlled rate of detonation and good sensitivity dueto the use of a petroleum oil in formulating the explosive, and to aprocess for manufacturing such explosive mixtures of controlled rate ofdetonation and sensitivity by blending the trimethylolethane trinitratewith inorganic nitrate in the presence of the petroleum oil in an amountto obtain the desired rate of detonation and good sensitivity.

Trimethylolethane trinitrate is a liquid explosive having a high rate ofdetonation and a low sensitivity. It has found use in blending withother explosive sensitizers of high sensitivity, so as to make themsafer to handle, without, however, reducing the sensitivity of the otherexplosive sensitizer to initiation by a detonator, as disclosed in U.S.Pat. No. 3,344,005, patented Sept. 26, 1967, to Bronstein and Griffith.However, the sensitivity of trimethylolethane trinitrate is such that ithas not come into widespread use except in admixture with otherexplosive sensitizers.

It has recently been discovered in private research by the presentinventor that trimethylolethane trinitrate can be formulated withinorganic nitrates to form explosive mixtures and gels which have a highrate of detonation and good sensitivity, using special mixingtechniques, and/or selected metal fuels. Such explosives frequently havea, higher rate of detonation than is desirable for certain kinds of workwhere low rate explosives are required, and their sensitivity may alsobe lower than is de sirable.

In accordance with the invention, trimethylolethane trinitrate explosivemixtures are prepared, based on an inorganic nitrate oxidizer andtrimethylolethane trinitrate as the principal if not the only explosivesensitizer. These explosive compositions have a controlled rate ofdetonation and good sensitivity, because of the use of petroleum oil informulating the explosive.

It has been determined in accordance with the inven tion that iftrimethylolethane trinitrate and the inorganic nitrate are blended witha petroleum oil, the resulting explosive mixture has a rate ofdetonation that is dependent upon the proportion of oil, and a goodsensitivity. Thus, by use of an appropriate amount of petroleum oil, anexplosive mixture can be obtained of any desired rate of detonation andsensitivity. The mixing can be carried out in the presence of the oil,and the larger the amount of oil above a minimum threshold amount, thelower 3,580,750 Patented May 25, 1971 the rate of detonation and thehigher the sensitivity, up to a threshold limit.

No explanation can be offered for this remarkable effect of petroleumoil on the sensitivity and rate of detonation of the resulting explosivemixture. Evidently, the petroleum oil has an effect on the physicalcondition of the trimethylolethane trinitrate and the inorganic nitratein the resulting explosive mixture, resulting perhaps from a coating ofthe inorganic nitrate by the oil, or in a solution of thetrimethylolethane trinitrate and oil, which coats the inorganic nitrate.It is also possible that a chemical or molecular association may occur.Whatever the reason, the effect on rate of detonation and on sensitivityis striking and unmistakable.

The explosive mixtures of the invention are formulated as dry ordry-appearing particulate mixtures. The trimethylolethane trinitrate andpetroleum oil although liquids are wholly absorbed on the solidparticles of inorganic nitrate and any other solid components that maybe present. Oil in an amount in excess of about 5% has an excessivedepreciating effect on rate of detonation, and consequently theexplosive mixtures of the invention are not formulated as slurries orgels in oil unless the amount of oil can be kept below 5%. Aqueousslurries can be formulated, however, in which the oil forms a part ofthe slurrying liquid, which is in excess of the amount that is absorbedby the solid ingredients, and is sufiicient to slurry the mixture.Usually, the amount of slurrying liquid does not exceed 30%.

Any inorganic nitrate can be employed as the oxidizer in thecompositions of the invention. Ammonium nitrate is the nitrate normallyused. However, other inorganic nitrates can be employed, alone or inadmixture with the ammonium nitrate. Nitrates of the alkali and alkalineearth metals, such as sodium nitrate, potassium nitrate, calciumnitrate, strontium nitrate, and barium nitrate, are exemplary inorganicnitrates. Mixtures of ammonium nitrate with alkali and/or alkaline earthmetal nitrates in proportions within the range from about 25 to about95% of ammonium nitrate, and from about to about 5% of the othernitrates, are preferred in many instances, because of their highexplosive power.

Mill and prill inorganic nitrates are quite satisfactory. The inorganicnitrate can be fine, coarse, or a blend of fine and coarse materials.

In addition to the trimethylolethane trinitrate and the inorganicnitrate, which are the essential ingredients, the explosive mixtures ofthe invention can include one or more solid fuels, such as a metal fuel,or a carbonaceous fuel, or both. Illustrative of particulate metals, forex ample, are aluminum powder, flake aluminum, atomized aluminum,ferrophosphorus, ferromanganese, and ferrosilicon. Aluminum is apreferred fuel because it tends to increase rate of detonation. A metalfuel when present will usually comprise from about 0.5 to about 30% ofthe mixture.

Useful solid carbonaceous materials are powdered coal, coal dust,charcoal, bagasse, dextrin, starch, wood meal, flour, bran, pecan meal,and similar nutshell meals. The carbonaceous fuel when present usuallycomprises from about 0.5 to about 30% of the mixture. Mixtures of suchfuels can also be used in amounts within the range from about 0.5 toabout 30%.

Sulfur can also be added. An amount of from about 0.5 to about 5% canincrease the rate of detonation.

Stabilizers can be included in an amount within the range from about 0.1to about 2% of the composition. Zinc oxide, ethyl centralite,diphenylamine, carbazole, calcium carbonate, aluminum oxide and sodiumcarbonate are useful stabilizers.

The petroleum oil can be any paramnic oil derived from petroleum that isnonvolatile at atmospheric temperatures, such as lubricating oil,petroleum oil No. 5, fuel oil, diesel oil, machine oil, SAE 10 to 60motor oils, signal oil, mineral seal oil, transformer oil, switch oil,Wool oil, flotation oil, emulsifying oil, spindle oil, turbine oil, andjournal oil. In general, the lower the viscosity of the oil, the lowerthe effectiveness. Therefore, oils having a viscosity within the rangefrom 10 to 30 SSU at 130 F. are preferred.

The proportion of oil used will control rate of detonation to a levelthat is lower and sensitivity to a level that is higher than thatobtainable in the absence of the oil. Thus, an excessive shattering ordetonating effect, or an unduly low sensitivity, of thetrimethylolethane trinitrateinorganic nitrate mixture can be reduced orincreased to any level appropriate to the explosive effect desired.

Normally, only very small amounts of oil are reeded. The minmiumthreshold amount can be as little as 0.05% by weight of thetrimethylolethane trinitrate-inorganic nitrate mixture; this will give anoticeable reduction in rate of detonation but higher amounts may beneeded to obtain a decrease in sensitivity. A decrease in sensitivity isnot usually observed until 1% or more oil is used. From 0.1% to about 3%is preferred, although amounts as great as 5% can be used before therate of detonation and sensitivity become so low that the composition isimpractical to use.

Thus, by appropriate amounts of oil, it is possible to control both rateof detonation and sensitivity, for, if low sensitivity is desired, arelatively large amount of oil, in excess of 1%, can be used, while ifhigh sensitivity is desired, a lesser amount of oil, less than 1%, canbe used.

Moreover, a low rate of detonation and high sensitivity can be obtained,despite the desensitizing effect of the oil, by mixing thetrimethylolethane trinitrate and inorganic nitrate at an elevatedtemperature, as is explained in more detail later, or by incorporatingparticulate aluminum.

Thus, the oil makes possible a controlled rate of detonation andsensitivity in trimethylolethane trinitrateinorganic nitrate explosives.The relative proportions of inorganic nitrate and trimethylolethanetrinitrate as well as any additional explosive sensitizers will dependupon the sensitivity and explosive effect desired, and the type ofexplosive mixture, and are not critical. These in turn are dependentupon the particular nitrate or nitrates used. For optimum effect, theinorganic nitrate is used in amounts within the range from about 50 toabout 90%, and the total explosive sensitizer including thetrimethylolethane trinitrate is an amount within the range from about toabout 50% The preferred ratio of nitrate to total explosive sensitizeris from about 5:1 to about 2:1. However, from about 35 to about 75%inorganic nitrate, and from about 25 to about 65% expolsive sensitizer,give quite satisfactory results in the explosive mixtures of theinvention.

The effect of the petroleum oil on rate of detonation is found with thetrimethylolethane trinitrate, but not with other explosive sensitizers,so far as is presently known. Consequently, the trimethylolethanetrinitrate is the major, if not the only, explosive sensitizer, andpreferably comprises at least 90% of the explosive sensitizer that ispresent. However, small amounts of other explosive sensitizers can beused, up to a maximum of 25% of the total explosive sensitizer, of whichdinitrotoluene, tritnitrotoluene, pentaerythritol tetranitriate,pentolite (an equal parts by weight mixture of pentaerythritoltetranitrate and trinitrotoluene), cyclonite (RDX), Composition B (amixture of up to 60% RDX, up to 40% TNT, and 1 to 4% wax), cyclotol(Composition B without the wax), nitrostarch, nitrocellulose, tetryl,smokeless powder, and carbine ball powder are exemplary. Nitrocelluloseis of particular interest in the formulation of gels, as is describedbelow.

For some purposes, the compositions of the invention can be formulatedas slurries, using an inert liquid such as Water as the suspendingliquid. The amount of liquid 4 that is used is more than is absorbed bythe solid ingredients, and suflicient to produce a slurry. The slurrycan have any desired consistency, from a thin, readily flowablematerial, to a viscous material of a semi-solid consistency. As littleas 5% liquid may suffice. Usually, not more than 30% liquid need beused.

In order to prevent large amounts of unabsorbed liquid from decreasingthe consistency unduly, a liquid-soluble or liquid-dispersible thickenercan be added to take up the liquid. The particular material employedwill depend upon the liquid that is used, water-soluble orwaterdispersible thickeners being used when water is the liquid, andoil-soluble or oil-dispersible thickeners being used When the oil is theliquid. Various gums, such as guar gum and cross-linked guar gum, can beused, as well as carboxymethylcellulose, methyl cellulose, psyllium seedmucilage, polyacrylamide, pregelatinized starches, such as Hydroseal 3B,as well as silica aerogels, finely-divided silicas, inorganic gellingagents such as alumina, attapulgite, bentonite, and like materials.

The explosive mixtures of the invention are prepared by blending in amixing vessel, which may desirably be equipped with a heating jacket forheating the components to a temperature within the range from about toabout F. The trimethylolethane trinitrate and inorganic nitrate oxidizerare added to the mixer, and mixing then effected at room or at anelevated temperature. If heat is used, the temperature is preferablywithin the stated range. Mixing at such temperatures tends to offset theeffect of the oil, and increases rate of detonation, so that heatingprovides a useful tool for a more precise control of rate detonation,while at the same time maintaining good sensitivity. It is not necessaryto heat the ingredients beyond the time required to ensure thoroughmixing, using from about fifteen minutes to about onehalf hour.

It is desirable to blend the trimethylolethane trinitrate, the inorganicoxidizer and the petroleum oil under these conditions without thepresence of the other explosive ingredients, so as to ensure an intimateassociation of the trimethylolethane trinitrate, inorganic nitrate andoil. Since, however, the trimethylolethane trinitrate and inorganicoxidizer usually by far compose the major proportion of the composition,in order to shorten the time of mixing, minor amounts of any otherexplosive ingredients that are to be present can also be added at thesame time. These additional components comprise the solid fuel, thestabilizer, and any additional explosive sensitizers. Alternatively,after mixing of the trimethylolethane trinitrate, inorganic oxidizer andoil is complete, the other explosive ingredients can be added andthoroughly blended with the mixture.

The base explosive mixture of the invention, composed oftrimethylolethane trinitrate, inorganic nitrate, and petroleum oil, canbe formulated to forma variety of explosives, including dry particulatemixes, such as permissible explosives, and gels, such as gelatindynamites, ammonia dynamites, and ammonia gels. Various types offormulations are illustrated in the examples.

The compositions of the invention are particularly useful in the form ofexplosive gels of the trimethylolethane trinitrate in combination withnitrocellulose. The nitrocellulose and trimethylolethane trinitrate arecombined with a volatile nitroparaffin solvent in a sufficient amount todissolve the nitrocellulose and the trimethylolethane trinitrate. Thesolvent is then removed from the resulting composition, and as this isdone, the solution thickens, and a gel of the trimethylolethanetrinitrate and nitrocellulose is obtained eventually. This gelcomposition is then formulated with additional explosive ingredients,including inorganic nitrate, and any other inorganic oxidizers, othersensitizing explosives, petrolerun oil, and other fuels, as describedabove, and can be brought to any desired consistency or physicalcondition.

Any type of nitrocellulose can be employed in the formulation of thesegels. A fully nitrated trinitrocellulose has the highest nitrogencontent (14.14% nitrogen) but the commercially availabletrinitrocelluloses having from 13.5 to 14% nitrogen are quitesatisfactory. Any nitrocellulose having from 0.5 to 3 nitro groups peranhydroglucose unit of the cellulose can be employed, with excellentresults. The preferred nitrocelluloses have from about 8% to about14.14% nitrogen.

The amount of nitrocellulose can be varied over a wide proportion,according to the sensitivity and consistency desired.

The nitroparafiin employed has no effect on the consistency of the finalgel, but the relative proportions of trimethylolethane trinitrate andnitrocellulose do. Inasmuch as the trimethylolethane trinitrate is aliquid, and the nitrocellulose is a solid, the larger the proportion oftrimethylolethane trinitrate, the greater the tendency of the final gelto be a thick, semi-fluid, thixotropic or soft gel. Very hard gels canbe obtained employing a large proportion of nitrocellulose. In general,the proportions of trimethylolethane trinitrate and nitrocelluloserequired for a gel of given hardness are best determined by trial anderror, because the hardness of the gel depends to a considerable extentupon the nitrogen content of the nitrocellulose.

Satisfactory hard explosive gels are obtained, of high sensitivity andadequate explosive power, when the composition contains from about 10 toabout 60 parts of nitrocellulose and from about 40 to about 90 parts oftrimethylolethane trinitrate. Soft gels are obtained when thenitrocellulose proportion is from 0.2 to 10 parts, and trimethylolethanetrinitrate is from 99.8 to 90 parts. Thus, the proportion oftrimethylolethane trinitrate can be varied to a considerable extent, andany proportion within the range from about 40 parts to about 99.8 partsof trimethylolethane trinitrate to from about 0.2 part to about 60 partsof nitrocellulose can be used.

The higher the proportion of nitrocellulose, the higher the sensitivityand explosive power of the composition. The trimethylolethane trinitratehas a desensitizing effect. In general, the upper limit on the amount oftrimethylolethane trinitrate will depend upon the explosive power andsensitivity that is desired, and the lower proportion will depend uponthe degree of desensitization of the nitrocellulose that is required,for the end use of the composition.

The nitroparafiin that is employed should be sufficiently volatile atatmospheric temperatures, or at a temperature below about 60 C., undervacuum, if necessary, so that it can be removed virtually quantitativelyfrom the composition after the trimethylolethane trinitrate andnitrocellulose have been dissolved therein, so as to form the desiredgel. Such nitroparafiins have from one to about six carbon atoms and onenitro group, and include nitromethane, nitroethane, l-nitropropane,2-nitropropane, l-nitrobutane and l-nitrohexane. These nitroparaffinshave a boiling point below about 150 C., but higher boilingnitroparaflins can be used, if they are removed under vacuum. They arenot explosive, and cannot be exploded with detonating caps, differing inthis respect from the trimethylolethane trinitrate. A furtherdistinction is their volatility, despite their high boiling point.Nitromethane, for example, the lowest molecular Weight compound of thisseries, has a boiling point of 101.2 C., and yet it is quantitativelyvolatilized from the solution on standing in the atmosphere for fromeight hours to three days. The relatively high boiling point isimportant to the formation of a gel, because it means that thenitroparafiin is only slowly volatilized from the solutions employed asa starting material in the preparation of the nitrocellulose gels. Aslow volatilization of the nitroparaffin may facilitate the formation ofthe final explosive gel.

The amount of nitroparafiin solvent is not critical. A suificient amountis employed to dissolve the nitrocellulose and trimethylolethanetrinitrate. Depending upon the solubility of the nitrocellulose and thetrimethylolethane trinitrate, as little as 20% by Weight of thecomposition can be employed. There is no upper limit, inasmuch as all ofthe nitroparaffin solvent will eventually be removed, but there isobviously no need to employ more than is necessary to dissolve thecomponents, since any excess nitroparaflin must also be evaporated informing the gel, with a resultant increase in the time required to formthe gel, as well as in the cost of its preparation. Thus, the upperlimit is normally not in excess of about 500% by weight of thenitrocellulose-trimethylolethane trinitrate.

Such gels in accordance with the invention can be employed with hotinorganic nitrate oxidizer in the formation of a wide variety ofexplosive formulations, including gelatin dynamites, smokeless powders,permissible explosives, and nitrocarbonitrate explosives.

Gelatin and semigelatin dynamites contain, in addition to thetrimethylolethane trinitrate-nitrocellulose gel, the inorganic oxidizerand a combustible material. The following is a general formulation:

Percent by weight Trimethylolethane trinitrate 5-95 Nitrocellulose0.1-15

Inorganic oxidizer 5-95 Combustible material or fuel (includingpetroleum oil) 0-25 Gelatin dynamites can be packaged in block form byfilling the solution of trimethylolethane trinitrate-nitrocellulose andany other components in the nitroparafiin solvent into containers of thedesired size, and then allowing the solution to gel by removal of thesolvent. This can be expedited by warming the containers in a vacuumoven. Then, after the gels have set, the containers are capped andsealed. Stick gelatin dynamites are easily prepared in this Way.

Some hard gelatin dynamites can be prepared by first mixing thenitrocellulose, nitroparaffin, and trimethylolethane trinitrate, andthen alowing the nitroparafiin to evaporate, forming a viscous liquid orgel. The viscous liquid or gel is then blended with the petroleum oil,and any other inorganic oxidizer, fuels and any additional sensitizersdesired forming a damp granular mixture, in which the liquid or gel iscoated or absorbed on the solid components. The mixture is then packagedin cartridges, using conventional dynamite pack machines.

Smokeless powders are in particulate form, and are based on thetrimethylolethane trinitrate-nitrocellulose gel as one component, incombination with the usual components to control the rate of burning.The types of smokeless powders that can be formulated, using the gelsand petroleum oil in accordance with the invention, include double basepowders and ball grain powders. Typical general formulations are asfollows:

Double base powder: Percent by weight Polyol polynitrate 560Nitrocellulose 5-95 Inorganic oxidizer 0-50 Combustible material or fuel(including petroleum oil) 0-5 Ball grain powder:

Polyol polynitrate 5-60 Nitrocellulose -40 Inorganic oxidizer 0-20Combustible material or fuel (including petroleum oil) 0-15 ofdispersion and the mesh size of the screen through which the compositionis passed,

The explosive mixtures of the invention are sufficiently sensitive sothat frequently they can be detonated with an ordinary initiator orblasting cap. However, when not, the compositions can be fired with theaid of a small booster charge. Combinations of the explosive mixtures aspowders together with an initiator and/or booster in the same containercan he prepared and marketed as a combined blasting agent. The explosivecompositions and the booster or initiator can be separately packaged asa composite in a single container, and can also be marketed in thisform. Any conventional initiator or booster charge available in the artcan be employed. Pentaerythritol tetranitrate, pentolite, tetryl andcyclonite, preferably in cast form, are exemplary booster charges.

The following examples in the opinion of the inventors represent thebest embodiments of the invention.

The power of the explosives of the examples was determined using thestandard tests for determining sensitivity, density, rate of detonation,and stick weight.

EXAMPLES 1-3 A group of four compositions was prepared, having theformulation set out in Table I. These were mixed hot (130 F.) usinggrained ammonium nitrate, and in the presence of from 0.3 to2% petroleumoil.

The control formulation is to be compared with Examples l to 3,respectively. The four compositions differ TABLE I Parts by weightExample Number Control 1 2 3 Composition:

Trirnethylolethane trinitrate. 20. 00 20.00 20. 00 20. 00 Ammoniumnitrate, ground 63.00 63.00 63.00 63.00 Sodium nitrate, mill 10.00 10.0010.00 10. 00 Flake aluminum 2.00 2.00 2.00 2.00 Wheat flour-.- 5. O0 5.00 5. 00 5. 00 Oil N0. 5 0. 1. 00 2. 00 Test results:

Sand density (g./cc.) 1. 19 1. 19 1. 19 1. 10 Sensitivity (1 inch x 4inches) Rate of detonation (1% inches x 8 inches) (meters/second) 4, 1123, 867 2, 866 1, 054 Stick weight (g.) (1 inches x 8 inohcs) 160 160 160160 N0. cap. 2 No. 6 cap.

rate of detonation than the compositions mixed cold. At 2% oil,sensitivity also is lower, but below 2%, sensitivity was not affected.

EXAMPLES 4-9 A group of six permissible explosive formulations wasprepared, containing flake aluminum as a metal fuel in addition to thecarbonaceous fuel and the other components. The ammonium nitrate,trimethylolethane trinitrate and petroleum oil were all mixed togetherat room temperature for twenty minutes, and the other ingredients werethen mixed in. These compositions had the followonly in the amount ofpetroleum oil. 30 ing formulation:

TABLE III Parts by weight Example Number 4 5 6 7 8 9 Composition:

Trimethylolethane triuitrate 7. 50 7. 50 15. 00 15. 00 20. 00 20. 00Ammonium nitrate, ground 61. 60. 10 56. 45 55. 10 53. 70 52. 60 Sodiumnitrate 10. 00 10. 00 10. 00 10. 00 10. 00 10. 00 Sodium chloride 10. 0010. 00 10. 00 10. 00 10. 00 10. 00 Zinc oxide 0. 30 O. 30 0. 30 0. 30 0.30 0. 30 o. 5-. 0. 76 0. 10 0. 75 0. 10 1. 00 0. 10 Bagasse 10. 00 10.00 5. 00 5. 00 0. 00 0. 00 Flake aluminum 0. 00 2. 00 0. 00 2. 00 0. 002.00 Wheat flour 0. 00 0. 00 2. 2. 50 5. 00 5. 00

Total 100. 00 100. 00 100. 00 100. 00 100. 00 100. 00

Test results:

Sand density (g./cc.) 665 0. 680 0. 880 0. 880 1. 310 1. 310 Stickweight (g.) (1% inches x 8 inches) 86 94 120 120 175 175 Sensitivity (1inch x 4 inches) (2) (1) 2) Rate of detonation (1% inches x 8 inches)(meters/second) 1, 630 1, 930 2, 364 2, 482 2, 072 2, 888

No.1cap.

2 No. cap.

It is evident all these compositions had low rates of detonation andgood sensitivity.

EXAMPLES 10-15 A group of six water-resistant permissible explosiveformulations was prepared, having the following composition:

TABLE IV Parts by weight Example Number 10 11 12 13 14 15 Composition:

Trimethylolethane trinitrate 7. 50 7. 50 15. 00 15. 00 20. 00 20. 00Ammonium nitrate, ground 59. 45 58. 10 54. 45 53. 10 51. 50. 60 Sodiumchloride 10. 00 10. 00 10. 00 10. 00 10. O0 10. 00 Zinc oxide 0. 30 0.30 0. 30 0. 30 0. 30 0. 30 Oil No. 5 0. 0. 10 0. 75 0. 10 1. 00 0. 10Bagasse 10. 00 10. 00 5. 00 5. 00 0. 00 0. 00 Flake a1llminllm-- 0. 002. 00 0. 00 2. 00 0. 00 2. 00 Jaguar 2. 00 2. 00 2. 00 2. 00 2. 00 2. 00Wheat flour 0. 00 0. 00 2. 50 2. 50 5. 00 5. 00

Total 100. 00 100. 00 100. 00 100.00 100. 00 100. 00

Test results:

Sand density (g. cc.) 0. 640 0. 640 0. 880 0. 880 1. 290 1. 290 Stickweight (1 8 inches x 8 inches) 88 88 120 172 172 Sensitivity (1 inch x 4inches) Rate of detonation (1% inches x 8 inches) (meters/second) 1, 4431, 572 2, 210 2, 358 2, 133 2, 836

N0. 3 cap. 2 No. cap. 3 No. 5 cap.

Each of these formulations was mixed fifteen minutes at the temperatureindicated in the table, with the trimethylolethane trinitrate, ammoniumnitrate, petroleum oil and other ingredients all being added togetherand mixed at room temperature.

All these compositions of the invention had low rates of detonation andgood sensitivity.

EXAMPLES 1 6-19 Four water-resistant ammonia dynamite formulations wereprepared. These formulations had the following composition:

TABLE V Parts by weight Example Number 14 17 18 19 Composition:

'Trimethylolethane trinitrate 14.00 14.00 14.00 14. Ammonium nitrate,grained 42. 10 51. 60 61. 10 65. 60 Sodium nitrate 35. 00 25. 00 15. 0010. 00 Zinc oxide 0. 30 0.30 0.30 0.30 Oil No. 0. 0.10 0.10 0. l0 Nutmeal (fine)- 5. 00 5. 00 5. 00 5. 00 Jaguar 100 2. 00 2. 00 2. 00 2. 00Flake aluminum 1.50 2.00 2 50 3.00

Total 100. 00 100. 00 100. 00 100. 00

Test results:

Sand desnity (g-Icc.) 1. 19 1. 1. 11 1. 11 Stick weight (g.) (1% inchesx 8 inches) 160 155 150 150 Ballistic pendulum value (No. 6

cap 8.5 9. 8 11. 2 11.8 Sensitivity (1 inch x 4 inches) Rate ofdetonation (1% inches x 8 inches) (meters/second) 2, 542 2, 803 2, 9033, 028

1 No. cap.

These compositions had low rates of detonation, and good sensitivities.

EXAMPLES 20-23 A group of four low density ammonia dynamites wasprepared. These formulations were as follows:

TABLE VI Parts by weight Example Number 20 21 22 23 C omposition:

Trimethylolethane trinitrate 14.00 14.00 14.00 14. 00 Ammonium nitrate,ground--. 42.10 51. 60 61. 10 65. 60 Sodium nitrate 35. 00 25.00 15.0010.00 Zinc oxide 0. 30 0.30 0. 30 0.30 Oil No. 5 0.10 0.10 0. l0 0. 10Bagasse 5.00 5.00 5.00 5. 00 Wheat flour 2. 00 2.00 2.00 2.00 Flakealuminumwn 1.50 2.00 2. 50 3.00

Total 100.00 100.00 100.00 100.00

Test results:

Sand density (g./cc.) 0.88 0.86 0.82 0.82 Stick weight (g.) (l hes x 8inches) 120 117 112 112 Sensitivity (1 inch x 4 inches) 0) Rate ofdetonation (1% inches x 8 inches) (meters/second) 2, 124 2, 161 2, 3032, 405 Ballistic pendulum value (No. 6

cap) 9. 1 10.2 11.2 11. 9

1 No. cap.

The trimethylolethane trinitrate, sodium nitrate and ammonium nitratewere blended with the other ingredients simultaneously, and the mixingtime at room temperature was one-half hour. All these compositions hadlow rates of detonation, and high sensitivity.

EXAMPLES 24-27 A group of four ammonia dynamites 'was prepared. Theseformulations had the following composition:

TAB LE VII Parts by weight Example Number 24 25 26 2 7 Composition:

Tnmethylolethane trinitrate 14. 00 14. 00 14. 00 Ammonium trinitrate,ground- 50. 70 60. 20 64. 70 Sodium nitrate 25. 00 15. 00 10. 00 Zincoxide 0. 30 0. 30 0. 30 011 No. 5 1.00 1.00 1. 00 Nut meal (fine) 5. 005. 00 5. 00 Wheat flour 2. 00 2. 00 2. 00 Flake aluminum 1. 50 2. 00 2.50 3. 00

Total 100. 00 100. 00 100. 00 100. 00 Testsresglgs:

an ensity (g [cc 1. 11 Stick weight (g 150 Balllsticpendulum Val 11. 5Sensitivity (1 inch x 4 inches) ate of detonation lnehes)(meters/second) 2, 787

N0. 1 cap. I No. cap.

These formulations were mixed at room temperature for one-half hour. Thetrimethylolethane trinitrate and ammonium nitrate and sodium nitratewere blended with the petroleum oil, and the remaining ingredients thenadded.

All four compositions had good sensitivity, and low rates of detonation.

EXAMPLE 28 A trimethylolethane trinitrate-nitrocellulose gel wasprepared by dissolving 4 parts of nitrocellulose (12.5% N) in parts ofnitromethane. To this was added with stirring 16 parts oftrimethylolethane trinitrate. The mixture was then spread in a thinlayer in a tray, allowing the nitromethane to evaporate, leaving apliable, clear gel.

A gelatin dynamite was prepared from this gel, having the followingformulation:

The ammonium nitrate was brought to F. and mixed hot with the gel. Theremaining ingredients were then mixed in. This composition had a goodsensitivity, a high density, and a low rate of detonation.

In the claims and in the specification, all proportions, percentages andparts are by weight.

Having regard to the foregoing disclosure, the following is claimed asthe inventive and patentable embodiments thereof 1. A trimethylolethanetrinitrate explosive composition having a controlled low rate ofdetonation and good sensitivity, comprising an explosive mixture of aninorganic nitrate oxidizer and trimethylolethane trinitrate as theprincipal explosive sensitizer, and petroleum oil in an amount to reducethe rate of detonation of the mixture.

2. A trimethylolethane trinitrate explosive composition in accordancewith claim 1, in which the inorganic nitrate is ammonium nitrate.

3. A trimethylolethane trinitrate explosive composition in accordancewith claim 1, in which the inorganic nitrate is a mixture of ammoniumnitrate and sodium nitrate.

4. A trimethylolethane trinitrate explosive composition in accordancewith claim 1, in which the inorganic oxidizer is in an amount from about50 to about 90%, and the trimethylolethane trinitrate is in an amountform about 10 to about 50%.

5. A trimethylolethane trinitrate explosive composition in accordancewith claim 4, comprising from 0.05 to about 5% petroleum oil.

6. A trimethylolethane trinitrate explosive composition in accordancewith claim 5, in which the amount of said oil is also suflicient toincrease sensitivity.

7. A trimethylolethane trinitrate explosive composition in accordancewith claim 6 comprising a solid carbonaceous fuel in an amount fromabout 0.5 to about 30% of the mixture.

8. A trimethylolethane trinitrate explosive composition in accordancewith claim 5 comprising a metal fuel in an amount from about 0.5 toabout 30% of the mixture.

9. A trimethylolethane trinitrate explosive composition in accordancewith claim 8 in which the metal fuel is aluminum.

10. A trimethylolethane trinitrate explosive composition in accordancewith claim 5 comprising an additional sensitizing explosive in an amountup to about 25% of the total sensitizing explosive.

11. A trimethylolethane trinitrate explosive composition in accordancewith claim 1, in which the trimethylolethane trinitrate is in the formof a gel with nitrocellulose.

12. A process for forming a trimethylolethane trinitrate explosivecomposition having a controlled low detonation and good sensitivity,comprising blending trimethylolethane trinitrate, an inorgani nitrateoxidizer at from 100 to 150 F. and mixing in a petroleum oil in anamount to reduce the rate of detonation of the mixture.

13. A process in accordance with claim 12, in which 12' the blending iscarried out in the presence of the oil, in an amount not exceeding about5% 14. A process in accordance with claim 12, wherein the inorganicnitrate is ammonium nitrate.

15. A process in accordance with claim 12, wherein the inorganic nitrateis a mixture of ammonium nitrate and sodium nitrate.

16. A process in accordance with claim 12, which includes blending asolid carbonaceous fuel with the blend of inorganic nitrate andtrimethylolethane trinitrate in an amount of from about 0.5 to about30%.

17. A process in accordance with claim 12, which includes blending ametal fuel with the blend of the inorganic nitrate and trimethylolethanetrinitrate in an amount of from about 0.5 to about 30% 18. A process inaccordance with claim 12, wherein the blending is continued for fromfifteen minutes to onehalf hour.

References Cited UNITED STATES PATENTS 3,344,005 9/1967 Bronstein et al.149-88X 3,423,356 1/1969 Grifiith 149-47X 3,489,623 1/1970 Griflith14991X BENJAMIN R. PADGETT, Primary Examiner S. I. LECHERT, JR.,Assistant Examiner U.S. Cl.'X.R.

$223353? UNITED STATES PATENT OFFICE CERTIFICATE OF CORRECTION PatentNo. 3, 580,750 D t d May 25, 1971 Inventofls) onouom L. GRIFFITH It iscertified that error appears in the above-identified patent and thatsaid Letters Patent are hereby corrected as shown below:

Column 3, line 16 "reeded" should be needed Column 3, line 17 "minmium"should be minimum Column 3, line 53 "expolsive" should be explosiveColumn 3, line 64 "tetranitriate" should be tetranitrate Column 6, line37 l "alowing" should be allowing Column 8, Table IV "Stick weight"should be Stick weight (g) Column 9, Table V "Example-Number 14" shouldbe Example {Number 16 Column 9 Table V, line 29 "desnity" should bedensity Column 10, line 74 "form" should be from Column 12, line 22"3,423,356" should be 3, 423, 256

Q 1 l v O Signed and sealed this 28th day of March 1 97.2.

(SEAL) 'Attest:

. f EDWARD M.-FLF1T0HER,JR.'

Attesting Officer ROBERT GOTT SCHALK Commissioner of Patents

